1. Field of the Invention
The present invention relates to medical devices for irrigation of wounds, and in particular to an improved splashback shield that enables a user to quickly, safely and economically flush a wound with multiple volumes of irrigant.
2. Description of the Related Art
Not so long ago there were no such things as sharps containers or needlestick exposure protocols. Wound irrigation was performed using a syringe and a needle or an IV catheter. The splash was a nuisance as were accidental needlesticks, but no one was really concerned about protection from deadly infectious diseases. Then, as time went by, more unlucky individuals became infected with HIV and hepatitis from occupational exposures to seropositive blood.
In 1990, the Zerowet® Splashield® product was introduced to emergency physicians at the SAEM (Society for Academic Emergency Medicine) meeting in Minneapolis. See prior art FIG. 1 of this application. The response was immediate and overwhelming. Since then, the Zerowet® Splashield® product 10 has become the preferred wound irrigation safety device of emergency physicians, nurses, NP's and PA's all across the country. In fact, it's found in nearly two of every three emergency departments nationally, and of course used internationally as well as in offices, clinics, prisons, military bases, convalescent homes and other settings too. The Zerowet® Splashield® was the subject of the Stamler U.S. Pat. Nos. 4,769,003 and Des. 344,133.
The Zerowet®& Splashield®as described in the Stamler patents and when properly used completely eliminates splash, while providing the optimal irrigation pressure recommended by nearly all textbooks covering the subject. In fact, many such textbooks recommend the Zerowet® Splashield® product by name. The cost of a Zerowet® Splashield® is less than the price of a typical IV catheter. Although some practitioners who think squeezing a bottle of saline works as well, studies show that this method generates only about 10% of the recommended pressure; the literature says “[d]on't do it!”
Over the years others have added “frills” in attempts to improve on the performance of the original Zerowet® Splashield® without any real success. Special egg shapes, carefully planned fluid impact angles, directional arrows, a myriad of exhaust ports and one (the Bionix® Igloo® Wound Irrigator) with a purported improved, multi-hole “Shower of Power” (but that product was later quietly pulled from the market, as they went back to a single hole design as originally introduced in 1990 by Dr. Stamler). See, e.g. the Morse U.S. Pat. No. 6,210,381 and the McKinnon U.S. Pat. No. 6,558,344. Note that Bionix, Westmed, Ethox and Busse companies are all licensees of the Stamler '003 patent.
In 1999 U.S. Pat. No. 5,860,947 was awarded to Stamler for a wound irrigation device 20 featuring a two-way check valve 22 with a short fill stem 24 to be installed between the splashback shield 10 and the three-ring “control” syringe 30. See prior art FIG. 2 of this application. This device, commercialized and known as the Klenzalac® wound irrigation system 20 is for treatment of larger, complex or heavily contaminated wounds including bites, crash injuries and open fractures. It allows irrigant 45 from a nearby basin 40 to be repeatedly and conveniently drawn directly into the syringe 30 and then dispensed through and inside the splashback shield 10.
When using the conventional prior art splashback shield 10 (FIG. 1) it is typically necessary to fill and refill the syringe at least a couple of times to completely and effectively irrigate average wounds. In doing so it is necessary to remove the splashback shield 10 while drawing in irrigant 45, or else air trapped under the shield 10 will initially be pulled into the syringe before the irrigant 45 (reducing the volume of irrigant to be dispensed). See prior art FIG. 8. The shield 10 is then replaced to irrigate the wound. While the Klenzalac® product 20 disclosed in the Stamler '947 patent is advantageous in avoiding this problem, it is extra equipment at an additional cost.